Generally speaking: yes/no, depends…. Regarding staying alive: Most hard hitting attacks can be avoided by dodging, positioning or other game mechanics (e.g. break bar). In T2 a good healer might be able to outheal these attacks, but in T4 or higher this is not possible. However, you will take some damage even if you play perfectly and thus need some heal in the group. Your responsibility as a DPS is to avoid all big attacks possible while doing the best DPS you can. Knowing the boss mechanics is vital for this.Also: the group should always stack on each other unless a mechanic forces them to split – if everyone is far apart the boons and heals will only reach a part of the group. Regarding support/boons: GW2 heavily rewards role specialization in group content.A tested and very efficient setup currently looks like this: Heal/boon hybrid (e.g. heal firebrand that also gives might, quickness and fury to the group)DPS/boon hybrid (e.g. Damage Renegade that also gives might and alacrity to the group)DPS (ideally at least one warrior to support the group with banners)DPSDPS The idea behind this is to ensure everyone has the important boons (25 might, fury, alacrity and quickness), you have enough heal/support as necessary and as much damage as possibleIf your role is not to specifically give an important boon (usually you need 25 might, fury, alacrity and quickness), then everything you equip and trait should maximize your damage. The only compromise you can do is to bring boss specific utility if needed (e.g. extra break bar damage, stability, mobility) However, this is only really relevant for high end content. In T2 fractals and below you can run a suboptimal build with missing boons or no clear role distinction and still have a smooth run. T4 fractals are also definately doable with another setup or a suboptimal setup, but some players like to have it as quick/easy as possible and will insist on the current meta composition. Have fun!